Fact Sheet

No.

Substance

Examples

Health Effects/Concerns

Is new standard more stringent?

Final  POI Air Standard (½ Hour Average)
(μg/m3)

1

Lead and Lead compounds

Uses:  Production of batteries, metal products and devices to shield X-rays.
Sources:  Paints, dyes, plastic coatings, and metal products, and release during industrial activities such as mining and smelting.

Exposure to lead can adversely affect many organ systems (e.g., nervous, digestive, renal). 
As well, there is a direct association between increased blood lead level and a decrease in children’s neurological function. 

Elevated blood lead levels have deleterious effects on brain function, including lowered intelligence, behavioural problems, and diminished school performance.    

Yes

1.5

2

Cadmium and Cadmium compounds

Uses: Production of nickel-cadmium batteries, paint pigments, and anti-corrosive coatings; manufacturing of electronic components and select metal alloys.
Sources: Mining, metal refining; combustion of fossil fuels.

Breathing air with lower levels of cadmium over long periods of time results in a build-up of cadmium in the kidney, and if sufficiently high, may result in kidney disease. The proposed standard  also provides additional protection of human health with respect to carcinogenicity.  Other effects that may occur after breathing cadmium for a long time
are lung damage and fragile bones.

Yes

0.075

3

Ethylene oxide

Uses: Disinfectant; sterilizing operations; chemical manufacturing.
Sources: Uncontrolled fugitive emissions or venting with other gases related to use as a chemical intermediate; combustion of hydrocarbon fuels; losses during disinfections of hospital equipment.

Ethylene oxide is a direct-acting mutagen and reacts with DNA.

Exposure can lead to an increase in the incidence of leukemia,
stomach cancer, cancer of the pancreas, and Hodgkin’s disease.

Yes
Guideline to Standard

0.6

4

n –Butanol

Uses: Organic solvent; intermediate in the manufacture of organic chemicals (most importantly: acetates, acrylates and glycol ethers); extractant in the manufacture of antibiotics, hormones and vitamins.
Sources: Majority of releases are from the motor vehicle and metal products industries

Animal studies have shown that exposure to n –Butanol can lead to reduced weight gain.

Other health effects in humans or animals at elevated concentrations can include central nervous system (CNS) depression, and irritation of the eyes and upper respiratory tract.

Guideline to Standard

2,760

5

Chlorine dioxide

Uses: Bleaching agent for wood pulp; disinfection of water; fungicide, bactericide in food industry.
Source: Pulp mills

Adverse effects on the respiratory system (i.e. blood vessel congestion and peribronchiolar
edema, which is an accumulation of excessive fluid) were identified in a study on rats.  A health effect in humans or animals at elevated concentrations is irritation of the respiratory system.

Yes

6

6

Chloroethane

Uses: Manufacture of dyes, chemicals, pharmaceuticals;  solvent; refrigerant; topical anaesthetic; production of propellants; formulation of insecticides
Sources: Emission during chemical production; burning waste; evaporation from solvents, aerosols and anaesthetic uses

A study with mice found that chloroethane inhalation exposure can lead to the delayed formation
of the skull bones. There is some evidence of carcinogenicity in female mice. Other health effects in humans or animals at elevated concentrations can include
CNS effects, and respiratory and cardio-vascular damage.

New standard

16,800

7

1,1- Dichloroethane

Uses: Intermediate in the manufacture of vinyl chloride and 1,1,1-trichloroethane;  coupling agent in anti-knocking gasoline;  metal degreasing and organic synthesis; solvent  in paint, varnish and finish removers
Sources: Industrial manufacturing and use processes

The critical effect considered in proposing the standard was based on a study that found that dichloroethane had adverse kidney effects in animals following inhalation exposure.
Other health effects in humans or animals at elevated concentrations can include
CNS depression, respiratory tract and dermal irritation, anaesthesia and cardiac
arrhythmia and possible carcinogenicity.

Yes
Guideline to Standard

495

8

Isobutanol

Uses: Solvent in paint and varnish removers; intermediate in organic synthesis in the pharmaceutical and pesticide industries; manufacture of fragrance essences
Sources: Motor vehicle industry

Inhalation of isobutanol caused a decrease in the response to external stimuli and damage to the CNS in rats. 

Other health effects in humans or animals at elevated concentrations can include gastrointestinal
effects, and irritation of the skin, eyes and throat.

Guideline to Standard

13,800

9

Methyl chloride

Uses: Production of agricultural chemicals and butyl rubber.
Sources: Organic chemical manufacturers, pulp industry

A short-term inhalation study using mice determined that methyl chloride can cause
lesions of the brain, accompanied by functional disturbances. 
Other health effects in humans or animals at elevated concentrations can include
CNS depression, and gastrointestinal related effects.

Yes
Guideline to Standard

960

10

Phosphoric Acid

Uses: The manufacture of fertilizers, soaps and detergents, inorganic phosphates and pharmaceuticals.

Respiratory tract effects (bronchiolar fibrosis) were identified in a sub-chronic study with rats.
Another health effect in animals at elevated concentrations is reproductive effects (shown as reduced body weights).

Yes

21

11

Propylene

Uses: Gasoline additive; manufacture of plastics; chemical intermediate in chemical manufacturing industry.
Sources: Emissions from combustion of gasoline, coal, wood, and refuse; petroleum refining sector and chemical manufacturing facilities

Studies have shown that inhalation of propylene can lead to abnormal cell transformation in the nasal cavity in rats.
An acute effect in humans or animals at elevated concentrations is simple asphyxiation (can cause unconsciousness or death by suffocation). 

New Standard

12,000

12

Sulphuric Acid

Uses: Manufacture of fertilizers, phosphoric and hydrofluoric acids, soaps and detergents, food additives, organic chemicals, explosives, plastics, rubber and storage batteries.
Sources: coal and oil-fired power plants (as SO2), mining and smelting industry, pulp and paper industry

Studies have shown that sulphuric acid produces negative bronchial effects (epithelial hyperplasia, which is thickening of the respiratory bronchiole walls) in animals.Other health effects in humans or animals at elevated concentrations can include irritation of the respiratory tract and altering the ability of the lung to clear particles. 

Yes

15

13

Total Reduced Sulphur (TRS) & Compounds: hydrogen sulphide  
mercaptans
dimethyl sulphide (DMS) 
dimethyl disulphide (DMDS)

Major sources of TRS: pulp & kraft mills, iron, steel and ferro-alloy, and petroleum & related products

Hydrogen sulphide
Uses: Reagent and intermediate in chemical production of other reduced sulphur compounds, sulphuric acid and extract of sulphides from metals;  metallurgic applications; agricultural disinfectants; production of heavy water
Sources: By-product of the refining of oil and petroleum and of the pulping process.

Mercaptans                         
Uses: Odorant in natural gas; an intermediate in the production of pesticides, jet fuel and in the synthesis of methionine and plastics.
Sources: By-product of the degradation of organic matter and of industrial processes.

Dimethyl sulphide                 Uses: Intermediate in production of various chemicals; gas odorant; solvent for anhydrous mineral salts

Dimethyl disulphide
Uses: Sulphating agent for certain industrial catalysts; food flavouring agent
Sources: Both DMS and DMDS are by-products of various industrial processes

A study on rats showed adverse respiratory system effects (nasal lesions of the olfactory mucous membrane). Other health effects of hydrogen sulphide in humans or animals at elevated concentrations can include eye, nose and respiratory irritations, rhinitis, wheezing; CNS effects such as motor activity, unconsciousness; respiratory paralysis; 
inflammation of the cornea; pulmonary edema, chest and eye pains; headache and dizziness.
Mercaptans, hydrogen sulphide, dimethyl sulphide (DMS) and dimethyl disulphide (DMDS) are chemicals with intense and  highly offensive odours.

Yes
Guideline to Standard

Yes

Yes

10
(for TRS)

      10
(for Hydrogen sulphide)

10
(for Mercaptans)

14

Trimethylbenzene (TMB) isomers
1,2,3-TMB
1,2,4-TMB
1,3,5-TMB

Uses: Gasoline additive; solvent in coatings, pesticides, cleaners, inks; chemical raw materials; paint thinners; the manufacture of perfumes, dyes, pharmaceuticals, resins
Sources: Vehicle emissions, motor vehicle industries; petroleum refining  plants, nonferrous foundries, plastic products manufacturers

The critical effect considered in proposing the standard was based on CNS effects in animals, which included behavioural effects such as , decreased pain sensitivity and impaired active
and passive avoidance in tests a known health effect in humans or animals at elevated concentrations is respiratory irritation.

New Standard
Guideline to Standard for 1,2,4-TMB

660

Kate Jordan
Communications Branch
(416) 314-6666